The Washington Obstetric Pharmacology Research Unit (WOPRU) represents a collaboration among two universities and four medical centers in the nation's capitol that is uniquely positioned to use population pharmacokinetic, pharmacokinetic-pharmacodynamic, clinical trials simulation, cutting edge in vivo and in vitro techniques to assess clinical pharmacology of important therapeutic agents and their effects in pregnant women and their offspring. Specifically, the WOPRU combines the basic research resources of Georgetown University (GU) (lead agency) and George Washington University (GWU) with the clinical strengths of MedStar Health (Washington Hospital Center [WHC] and Georgetown University Hospital [GUH]), GWU Hospital, and Children's National Medical Center (CNMC). Our hospitals are strategically placed throughout the DC metropolitan area, and are closely associated with the respective surrounding communities. The WOPRU obstetricians deliver over 7,000 babies from women who represent a broad spectrum of social, economic, ethnic, racial and cultural backgrounds with a large proportion of these pregnancies being high risk. The WOPRU institutions have an excellent track record of providing care and recruiting patients into clinical trials from our diverse community. The faculty of the WOPRU represent a team of highly motivated basic scientists and clinical investigators who are enthusiastically approaching the prospect of becoming a new center for OPRU. They are experienced investigators in a multitude of basic science and clinical disciplines with a unique combination of strengths in pharmacometrics, pharmacodynamics, pharmacogenetics, drug metabolism, therapeutic drug monitoring, proteomics, genomics and biostatistics in conjunction with significant experience in multi-center clinical trials. The administration, and the basic science and clinical investigators of the WOPRU institutions are unanimous in their eagerness to support and participate in the future OPRU network.